1. Technical Field
The present invention relates to a chain guide which presses an endlessly connected chain and thereby gives tension to the chain so as to prevent the slacking of the chain, and also relates to a chain tensioner device.
2 Background Art
A chain tensioner device is provided with chain guides which are brought into contact with middle portions of a chain endlessly provided around drive and driven sprockets and running at high speed, and is configured to press at least one of the chain guides against the chain in the direction substantially perpendicular to the running direction of the chain to thereby apply tension to the chain so as to prevent the chain from slacking. The chain tensioner device is used for a timing chain, or the like, of a valve driving device of an engine.
The chain guide is configured to guide the chain while being in contact with the chain, and hence sliding resistance is generated due to friction between the chain guide and the chain, causing a problem of an increased noise and mechanical loss.
Known techniques for suppressing the noise and mechanical loss of the chain guide include those described in Patent Literature 1 and Patent Literature 2. The chain guides described in Patent Literature 1 and Patent Literature 2 are formed in a curved shape along the running direction of the chain, in which rollers are arranged at a sliding-surface portion which is brought into contact with the chain, and the rollers are rolled by being pressed against the chain running at high speed, and thereby the sliding resistance is reduced.